Smallest stud depth for aqua panel

[therhinouk]

All the walls bar one of our bathroom are stud walls. Typically the wall that is block work is the wall I want to install aqua panels (as that's where the bath / shower will be).

My question is what is the min depth the studs can be to install aqua panels? I know they recommend building up the studs using 2"x4"s but room depth is a little tight so could you use slightly small depth batons on the block work (like 1" square or even 2"x3"s)?

Many thanks

(sorry for the repost, someone pointed out that his would be a better place for this kind of post)

 

[Karis]

In spite of what Knauf say, you can fix Aquapanels directly to the wall.

 

[therhinouk]

Ok, that aside I'm going to build up a stud anyway. So as I'm going to be doing that what min depth does there have to be?

 

[Karis]

The battens must be deep enough to accept the length of screws you’re going to use. If using Aquapanel screws which (I believe) are 40mm long, you would need a 30mm deep batten. The screws should penetrate a minimum 2 x the thickness of the panel so the minimum length screws would be 38mm & the batten depth required would be 26mm to prevent the screws binding on the wall. Battens should be 50mm wide, or the screws will be too close to the edge of the boards.

But why choose battens over direct fixing?